Locomotive boiler throat sheet construction



Feb. 13, 1934. w so 1,946,996

LOCOMOTIVE BOILER THROAT SHEET CONSTRUCTION Filed Oct. 14, 1933 2 Sheets-Sheet l INVENTOR /4 George M l Vf/son AT RNEY Feb. 13, 1934. G. M. WILSON 1,946,995

LOCOMQTIVE BOILER THROAT SHEET CONSTRUCTION Filed Oct. 14, 1933 2 Sheets-Sheet 2 INVENTOR 8 Geo/7e A/[VVf/son ATT NEY An obect of the invention is to provide an imthey will respectively engage, one with the for- 60 l() A further object is to provide an improved forwardly and the forwardly extending flange is {36 which the present invention is concerned, the will enable the desired results that have been set 80.

Patented Feb. 13, 1934 1,946,996

one]: STATES PATENT OFFICE LOCOMOTIVE BOILER THROAT SHEET CONSTRUCTION George M. Wilson, Schenectady, N. Y. Application October 14, 1933. Serial No. 693,691

5 Claims. (Cl. 122-58) This invention relates to steam boilers of the portions and to thereby materially decrease the type used in locomotives, and particularly to an degree of .abruptness of warping necessary at improved throat sheet construction for such these portions for producing the required ofiset in boilers. the two flanges to position the flanges where proved throat sheet construction for a locomotive ward margin of the fire box section and the other steam boiler especially adapted to accommodate With the rear margin of the barrel section.

longitudinal contractions and expansions of the In the exemplification of the invention hereboiler. inafter described the throat sheet is extended throat sheet construction of the character aforeconsequently correspondingly extended forwarddescribed particularly adapted to facilitate cir- 1y, as is also the rear margin of the barrel section culation of water from one boiler section to anengaged by the forwardly extended flange. other. Obviously, instead of this forward extension of 15- Other and further objects of and advantages the throat sheet, it can be extended rearwardly 7Q achieved by the present invention will be apy a Corresponding r d ex ion of the parent from the description of an approved rearwardly extending side flanges and the forexemplification thereof hereinafter set forth. Ward margin of the fire box section, or if de- While the present invention is not confined to sired, the sh t a be d d both wa hr go any particular design of throat sheet, the cond rearwardly With Corresponding pp p ate ventional design which is herein referred to conextensions of the flanges and a s. t is tains features common to all designs subject to therefore t be understood t at the app nd d the improvements of the present invention, claims unless otherwise restricted are intended to In the conventional boiler of the type with over a hro sheet e n d i ny way that forward margin of the fire box section and the forth t e a e rear margin of the barrel section are in direct In the a mpanying drawing Figure 1 is a engagement over substantially the upper half of diagrammatic side elevation of a locomotive boiler the barrel section and the margins begin to (11- including a throat sheet construction embodying 3o verge downwardly at substantially the horizontal the Present ihventieh; 2 is an ged, fra 85 center line of the barrel section. The purpose of y, Side elevation of t e boiler shown in the throat sheet is to connect the respective Fig. 1; Fig. 3 1S a half front view of the structure margins extending downwardly from said hori- Shown in Figs- 4 t0 9 are horizontal, 0 zontal center line, and to enclose the boiler be,- gitlldinal, a y, Sectional views of the tween these margins. To accomplish this the Structure, taken on e es IVIV to IXIX 90 throat sheet is shaped at each side to provide a inclusive, respectively, of 3; Fig. 10 is an enrearwardly extending flange, and in front to prolal'ged, perspective V ew Of the throat sheet of vide a forwardly extending flange, the rearwardly the present ihventien; and 11 is a a ed, extending flanges being for connection ith th perspective view of the rear portion of the loco- 40 forward margin of the fire box secti and t motive boiler barrel section to which the throat 95 forwardly extending flange for connection with sheet of the present invention is attached. O V the rear margin of the barrel section throughout The Present invention is hown in connection the converging portions of said margins at h with a locomotive steam boiler of the convenside of t boiling tional type indicated generally by the numeral 1,

To connect th converging margins t is neceswhich includes the usual fire box section 2 and 100 sary to warp the throat sheet between its flanges barrel section 3 connected thereto at its forward inamanner to produce reverse curves therein, in Such b01161 Sections being 01d and well horizontal planes, and obviously where there is known in the art, a detailed description h e f very little surface in comparison to the thickness will not be herein includedof the throat sheet, it is exceedingly diflicult t The outer front sheet of the fire box section, l05 impart the necessary warping without unduly taxthat is to say the throat sheet 4, (see particularly ing the sheet. The sheet diminishes in area Fig. 10) comprises a body portion 5 which is gradually upwardly at each side as the flanges disposed transversely of the boiler at the forward converge, and the gist of the present invention is end of the fire box section and extends upwardly to enlarge the throat sheet at its upper side from the bottom of the fire box section until it meets the bottom and sides of the barrel section 3 at the rear end thereof. Rivet holes 6 are provided in the lower margin of the portion 5 and this margin is secured by rivets (not shown) passed through these holes, into the fire box section mud ring, a portion of which is indicated at 7 in Fig. 10. The throat sheet is turned forwardly at the portion thereof above the body portion 5, engaging the bottom portion of the barrel section indicated at 8, and providing a curved flange 9 which is suitably secured to the portion of the barrel section indicated at 8 by rivets (not shown), registering rivet holes l0 and 11 being provided in the portion of the bare rel section at 8 and the flange 9 respectively for this purpose. At the sides of the body portion 5, the throat sheet is turned rearwardly, providing substantially vertical, longitudinally extending, side flanges 12. The side flanges 12 extend from the bottom of the fire box section to the top of the throat sheet at a location approximately just above the center line. of the barrel section. Rivet holes 13 are provided in the side flanges, and these flanges are secured to the outer side sheets 14 of the fire box section by means of rivets (not shown) passed through the holes 13 and corresponding holes 15 provided in the sheets 14.

The curved flange 9 extends upwardly at its opposite sides providing substantially vertical portions adjoining the upper portions of the flanges 12. The upper portions indicated at 16 of the throat sheet are extended forwardly, providing wings or extensions 1'7 which engage the sides of the barrel section, being curved in conformity therewith. Rivet holes 18 are formed in the wings 1'7 and in the upper margins of the throat sheet portions immediately adjacent thereto. The barrel section 3 is cut away at its opposite sides, below the barrel center line, as in-. dicated at 19. Rivet holes 20 corresponding to the holes 18 are formed in the margins of the section 3 around the cutaway portions, where the wings I! engage the barrel section, suitable rivets (not shown), being disposed through the holes 18 and 20, securing the parts together. As indicated at 21 rivet holes are provided around the entire rear margin of the upper portion of the barrel section 3, corresponding holes being provided in the adjacent fire box section sheet portions, and rivets (not shown) being passed through these holes, securing these adjacent portions together in the usual manner.

At approximately the center line of thebarrel section, the side sheets 14 of the fire box section are tangent to the respective sides of the barrel section and the respective adjacent forwardly and rearwardly extending flange portions, at the opposite sides of the throat sheet, accordingly approach each other as they near this location, and are aligned with each other at this location as shown in Fig. 4. That is, on each side of the boiler the fire box sheet 14, the flange 12, the portion indicated at 16, and the barrel section side are in a substantially straight horizontal line at this location. It is just below this location that cracks in the throat sheet usually occur, as the result of expansions and contractions of the fire box section and barrel section.

It will be understood that the expansions and contractions of the boiler sections are due to heating and cooling and are greatestin a longitudinaldirection. Thus, as the upper portions of the throat sheet form the connection, at this location, between the fire box section and the barrel section, they must adjust themselves accordingly to accommodate these expansions and contractions. Such adjustments in throat sheet constructions of designs such as heretofore employed usually result in a weaving action, which sets up great strains in the throat sheet, and frequently results in cracking the sheet at the points of greatest strain.

In Figs. 4 to 9 there are illustrated sections showing the curves of the throat sheet construction of the present invention at various locations throughout a zone extending downwardly from substantially the center of the barrel section. In Figs. 5 to 8 inclusive, there are indicated, in broken lines, the curves of a throat sheet of the usual type, heretofore employed at the various respective locations, and in Fig. 2 there is indicated by broken lines the usual location of the lap joint between the throat sheet and barrel section. It will be apparent that the throat sheet construction of the. present invention is lengthened, that is, it is provided with the wings 1'7 at the portions thereof which connect with the barrel section from the barrel section center line to a line some distance below, covering a zone where the greatest strains occur. Thus, while as in usual practice the throat sheet of the present construction is connected to the barrel section by rivets, in the present instance the riveted connections of the portions covering a zone immediately below the barrel section center line are moved further forward than in usual practice. Above and below the wings 17', the connection is brought back to the usual positions, that is, it conforms with the shape of the throat sheets commonly used.

It is, noted that the usual practice is followed in the securing of the throat sheet with its side flanges placed at the inner sides of the outer flre box sheets and its forwardly extending flange placed at the outer side of the barrel section, as clearly shown in Figs. 4 to 9 inclusive.

Byelongating the throat sheet in this manner, greater space is provided in which the directions of; the curvature of the throat sheet at the sides of the boiler must be changed, and thus curves of easier sweep than those heretofore employed in throat sheets, may be used. With such construction it will be apparent that the throat sheet may more freely adjust itself in order to accommodate the longitudinal expansions and contractions hereinbefore mentioned, so that cracking of the sheet as a result of such expansions and contractions will be avoided or reduced to a minimum.

Further, by virtue of this relative gradual curvature of the throat sheet, circulation of water from the barrel section to the fire box section past the throat sheet will be facilitated, that is to say the circulation will not be obstructed by abrupt irregularities in the contour of the throat sheet, such as are present in designs of the prior art.

While there has been hereinbefore described an approved embodiment of the present invention, it will be apparent to. those skilled in the art that many and variouschanges and modificationsirr degree, form, structure and arrangement may be made without departing from the spirit of the invention and it will be understood that all andany, such, changes and modifications are contemplated as a partof the present invention. The invention. claimed and desired, to be. se-. curedby Letters Patent is:

1. A steam boiler comprising a fire box section;

a barrel section disposed forwardly of said fire box section with its bottom higher than the bottom of said fire box section; and a throat sheet connecting said sections having a body portion transversely disposed at the forward end of said fire box section and extending upwardly from the bottom thereof to said barrel section, side flanges at the opposite sides of said body portion extending upwardly beyond said body portion, said side flanges extending rearwardly of said body portion and being connected with the respective sides of said fire box section, and a curved flange at the top of said body portion having side portions extending upwardly beyond said body portion adjacent the upper portions of the respective side flanges, said curved flange extending forwardly of said body portion and being connected with the bottom and sides of said barrel section, said side portions of said curved flange and the respective adjacent rearwardly extending side flanges approaching alignment with each other as they approach the horizontal center line of said barrel section and said throat sheet being widened between each of said side portions of said curved flange and its adjacent side flange above said body portion to provide relatively gradually diminishing curves therein from the body portion upwardly.

2. A throat sheet comprising a body portion adapted to be transversely disposed at the forward end of a boiler fire box section and to extend upwardly from the bottom thereof to a boiler barrel section; side flanges at the opposite sides of said body portion extending upwardly above said body portion, said side flanges extending rearwardly of said body portion for engagement with the respective sides of said fire box section; and a curved flange at the top of said body portion having side portions extending upwardly beyond said body portion adjacent the upper portions of the respective side flanges, said curved flange extending forwardly of said body portion for engagement with the bottom and sides of said barrel section, said upwardly extending side portions of said curved flange adjoining the upper portions of said respective side flanges and being extended further forwardly than the lower portion of said curved flange, whereby said upper portions of said side flanges and the respective adjacent side portions of said curved flange gradually approach alignment with each other in an upward direction.

3. A steam boiler comprising a fire box sec tion; a barrel section disposed forwardly of said fire box section with its bottom higher than the bottom of said fire box section; and a throat sheet connecting said sections having a body portion transversely disposed at the forward end of said fire box section and extending upwardly from the bottom thereof to said barrel section, side flanges at the opposite sides of said body portion extending upwardly above said body portion, said side flanges extending rearwardly of said body portion and being connected with the respective sides of said fire box section, and a curved flange at the top of said body portion having side portions extending upwardly beyond said body portion adjacent the upper portions of the respective side flanges, said curved flange xtending forwardly of said body portion and being connected with the bottom and sides of said barrel section at the rear end thereof, said upwardly extending side portions of said curved flange adjoining the upper portions of said respective side flanges and being extended further forwardly than the lower portion of said curved flange and said rear end or said barrel section having a contour corresponding to the contour of said curved flange, whereby the connections of said upwardly extending side portions of said curved flange with the respective sides of said barrel section are disposed forwardly of the connection of the lower portion of said curved flange with said barrel section.

4. A throat sheet for connecting a semi-boxshaped fire box boiler section and a barrel boiler section, adapted to extend from the bottom of the fire box section to substantially the horizontal center line of the barrel section, comprising oppositely disposed side margins for attachment to said fire box section and a margin forward of said side margins for attachment to said barrel section, the upper side portions of said sheet being widened between said margins.

5. A throat sheet for connecting a semi-boxshaped fire box boiler section and a barrel boiler section, adapted to extend from the bottom of the fire box section to substantially the hori zontal center line of the barrel section, comprising oppositely disposed side marginsfor attachment to said fire box section and a margin forward of said side margins for attachment to said barrel section, the upper portions of said last mentioned margin being extended forwardly providing thereby widened upper portions of said sheet.

GEORGE M. WILSON. 

